As a result of increased clinical use of varieties of antibiotic chemotherapeutic agents in recent years, symptoms primarily comprising diarrhea are today being reported in large numbers.
Such diarrheal symptoms are typically caused by pseudomembranous colitis. Virus theories, allergy theories, etc. have been propounded as the mechanism of occurrence of grave colitis of this type. However, as a result of the study on enterotoxin, an exotoxin produced by enterobacteria, it has recently come to be thought that the principle cause of such colitis is the proliferation of a certain toxogenic bacteria induced by the change in the enteric bacterioflora caused by administration of chemotherapeutic agents.
For instance, a study by Ueno et al on D-1 toxin and D-2 toxin, both of which are produced by Clostridium difficile, a common anaerobic enterobacterium, was published in Biochemistry International, Vol. 2, No.6, pp. 629-635, 1981. According to this report, D-1 and D-2 impair permeability of cells, injure HeLa cells and are a direct cause of pseudomembranous colitis.
Clinically, pseudomembranous colitis causes prolonged symptom of watery diarrhea containing mucus, inviting general hyposthenia, sometimes resulting in death.
In the clinical diagnosis of this disease, an S-shape colonoscope is used, biopsy of the rectum is carried out, and detection of pathogenic bacteria from feces is required. These diagnostic tests require sophisticated techniques and consume much time.
We pursued an extensive study to find ways for diagnosing pseudomembranous colitis more simply and quickly with higher accuracy. As a result of this study, we achieved this invention.